function value = p11_f ( dim_num, point_num, x ) %*****************************************************************************80 % %% P11_F evaluates the integrand for problem 11. % % Dimension: % % DIM_NUM is arbitrary. % % Region: % % 0 <= X(1:DIM_NUM) <= 1 % % Integrand: % % exp ( sum ( abs ( 2 * X(1:DIM_NUM) - 1 ) ) ) % % Exact Integral: % % ( E - 1.0 )**DIM_NUM % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 02 June 2007 % % Author: % % John Burkardt % % Reference: % % Thomas Patterson, % [Integral #2], % On the Construction of a Practical Ermakov-Zolotukhin % Multiple Integrator, % in Numerical Integration: Recent Developments, Software % and Applications, % edited by Patrick Keast and Graeme Fairweather, % D. Reidel, 1987, pages 269-290, % LC: QA299.3.N38. % % Parameters: % % Input, integer DIM_NUM, the dimension of the argument. % % Input, integer POINT_NUM, the number of points. % % Input, real X(DIM_NUM,POINT_NUM), the evaluation points. % % Output, real VALUE(POINT_NUM), the integrand values. % value(1:point_num) = 0.0; for point = 1 : point_num value(point) = exp ( sum ( abs ( 2.0 * x(1:dim_num,point) - 1.0 ) ) ); end p11_i4 ( 'I', '#', point_num ); return end